- Part A: Cohorts of 5-10 patients receive escalating doses of GM-CSF until the optimal immunostimulatory dose (ISD) is determined. The optimal ISD is defined as the dose at which at least 7 of 10 patients experience immunostimulation. Once the optimal ISD is determined, 10 patients receive aerosolized GM-CSF at a dose halfway between the optimal ISD and the preceding dose. Dose escalation is discontinued if at least 2 of 5 or at least 4 of 10 patients on a particular dose level experience dose-limiting toxicity.